Emissive properties of quantum emitters coupled to ultra-thin epsilon-near-zero films*

Plasmonic substrates are commonly used for enhancing emissivity of quantum emitters such as atoms, molecules or quantum dots in QED photochemistry and surface-enhanced spectroscopies. Substrates made of novel materials such as hyperbolic metamaterials, 2-dimensional, and epsilon-near-zero (ENZ) materials have emerged recently. Here, we present our study of the emissive properties of classical and quantum emitters placed on the surface of ultra-thin ENZ films which support plasmon polariton modes. Quantum emitters with the emission wavelength matching the ENZ polariton wavelength show enhanced emission rates due to increased local density of optical states. Active control of the emitters coupled to a gated ENZ-insulator-metal heterostructure is discussed. Strong coupling between polariton modes in the heterostructure is observed, which is tunable by an external electric field. Quantum emission switching between polariton branches of the hybrid mode is predicted.